51单片机1602lcd实现时间显示，可调时间和闹钟c语言

以下是51单片机1602lcd实现时间显示，可调时间和闹钟的C语言代码：

#include <reg51.h>
#include <intrins.h>

#define uchar unsigned char
#define uint unsigned int

sbit RS = P2^6;
sbit RW = P2^5;
sbit E = P2^7;
sbit K1 = P3^2;
sbit K2 = P3^3;
sbit K3 = P3^4;
sbit K4 = P3^5;

uchar code table[] = "2019-01-01 00:00:00";
uchar time[20];

uchar sec,min,hour,day,month,year,week;
uchar alarm_sec,alarm_min,alarm_hour;

void delay(uint ms)
{
    uint i,j;
    for(i=0; i<ms; i++)
        for(j=0; j<125; j++);
}

void write_com(uchar com)
{
    RS = 0;
    RW = 0;
    P0 = com;
    _nop_();
    E = 1;
    _nop_();
    E = 0;
    delay(1);
}

void write_data(uchar dat)
{
    RS = 1;
    RW = 0;
    P0 = dat;
    _nop_();
    E = 1;
    _nop_();
    E = 0;
    delay(1);
}

uchar read_data()
{
    uchar dat;
    RS = 1;
    RW = 1;
    E = 1;
    _nop_();
    dat = P0;
    E = 0;
    return dat;
}

void init()
{
    write_com(0x38);
    write_com(0x0c);
    write_com(0x06);
    write_com(0x01);
    delay(5);
    write_com(0x80);
}

void lcd_display(uchar *p)
{
    while(*p != '\0')
    {
        write_data(*p++);
    }
}

void ds1302_write(uchar dat)
{
    uchar i;
    for(i=0; i<8; i++)
    {
        SCK = 0;
        DSIO = dat & 0x01;
        dat >>= 1;
        SCK = 1;
    }
}

uchar ds1302_read()
{
    uchar i,dat=0;
    for(i=0; i<8; i++)
    {
        SCK = 0;
        if(DSIO)
            dat |= 0x01 << i;
        SCK = 1;
    }
    return dat;
}

void ds1302_init()
{
    uchar i;
    CE = 0;
    SCK = 0;
    ds1302_write(0x8e);
    ds1302_write(0x00);
    for(i=0; i<8; i++)
        ds1302_write(table[i]);
    CE = 1;
}

void ds1302_read_time()
{
    uchar i;
    CE = 0;
    ds1302_write(0xbe);
    for(i=0; i<7; i++)
        time[i] = ds1302_read();
    CE = 1;
    sec = time[0] & 0x0f;
    sec += (time[0] >> 4) * 10;
    min = time[1] & 0x0f;
    min += (time[1] >> 4) * 10;
    hour = time[2] & 0x0f;
    hour += (time[2] >> 4) * 10;
    day = time[3] & 0x0f;
    day += (time[3] >> 4) * 10;
    month = time[4] & 0x0f;
    month += (time[4] >> 4) * 10;
    week = time[5] & 0x07;
    year = time[6] & 0x0f;
    year += (time[6] >> 4) * 10;
}

void ds1302_write_time()
{
    uchar i;
    CE = 0;
    ds1302_write(0x8e);
    for(i=0; i<7; i++)
        ds1302_write(time[i]);
    CE = 1;
}

void set_time()
{
    uchar i;
    for(i=0; i<20; i++)
    {
        time[i] = 0;
    }
    lcd_display("Set Time:");
    write_com(0xc0);
    lcd_display("YYYY-MM-DD-hh-mm-ss");
    write_com(0xc3);
    K1 = 0;
    while(K1 == 0);
    for(i=0; i<19; i++)
    {
        if(i == 4 || i == 7 || i == 10 || i == 13 || i == 16)
        {
            write_com(0xc2+i);
            K1 = 0;
            while(K1 == 0);
        }
        else
        {
            write_com(0xc2+i);
            K1 = 0;
            while(K1 == 0)
            {
                if(i == 15)
                    time[i] = (time[i]+1) % 60;
                else if(i == 12)
                    time[i] = (time[i]+1) % 24;
                else if(i == 9)
                    time[i] = (time[i]+1) % 31 + 1;
                else if(i == 6)
                    time[i] = (time[i]+1) % 13 + 1;
                else if(i == 3)
                    time[i] = (time[i]+1) % 100;
            }
        }
        if(i == 18)
            break;
        delay(50);
    }
    write_com(0x01);
}

void set_alarm()
{
    uchar i;
    for(i=0; i<20; i++)
    {
        time[i] = 0;
    }
    lcd_display("Set Alarm:");
    write_com(0xc0);
    lcd_display("HH-MM-SS");
    write_com(0xc3);
    K1 = 0;
    while(K1 == 0);
    for(i=0; i<8; i++)
    {
        if(i == 2 || i == 5)
        {
            write_com(0xc2+i);
            K1 = 0;
            while(K1 == 0);
        }
        else
        {
            write_com(0xc2+i);
            K1 = 0;
            while(K1 == 0)
            {
                if(i == 7)
                    alarm_sec = (alarm_sec+1) % 60;
                else if(i == 4)
                    alarm_min = (alarm_min+1) % 60;
                else if(i == 1)
                    alarm_hour = (alarm_hour+1) % 24;
            }
        }
        if(i == 7)
            break;
        delay(50);
    }
    write_com(0x01);
}

void main()
{
    init();
    ds1302_init();
    while(1)
    {
        ds1302_read_time();
        sprintf(time, "%04d-%02d-%02d %02d:%02d:%02d", 2000+year, month, day, hour, min, sec);
        write_com(0x80);
        lcd_display(time);
        delay(500);
        if(alarm_hour == hour && alarm_min == min && alarm_sec == sec)
        {
            write_com(0x01);
            lcd_display("Alarm!!!");
            delay(200);
            write_com(0x01);
        }
        if(K2 == 0)
            set_time();
        if(K3 == 0)
            set_alarm();
    }
}

这个代码实现了一个简单的时钟，可以通过按下K2键设置当前时间，按下K3键设置闹钟时间。每秒钟LCD屏幕上显示当前时间，并且如果闹钟时间到了，LCD屏幕上会显示"Alarm!!!"。